Iran's new president, in sharp contrast to his predecessor, is expected to give a conciliatory speech. The question is how sincerely Iran wants compromise.

Iranian President Hassan Rouhani was elected in June after a campaign that… (Atta Kenare / AFP/Getty…)

WASHINGTON — For the last six years, the Iranian president's speech at the annual gathering of the United Nations has been met by a ritual walkout of Western diplomats. This year, they're likely to hang around till the end — and some may even applaud.

Instead of the angry Holocaust-denying diatribes of former President Mahmoud Ahmadinejad, his soft-spoken successor, Hassan Rouhani, is likely to give a conciliatory address to world leaders this week. It will be closely watched for signs that he is willing to thaw relations with the West.

Western diplomatspredict that Rouhani's speech Tuesday at the U.N. General Assembly will include an important gesture, perhaps an acknowledgment of the Holocaust. U.S. officials would like to see him go further during his five-day visit, possibly by consenting to direct talks with Washington for the first time since diplomatic relations were ruptured by the 1979 Islamic Revolution.

The White House says it has not scheduled a meeting between President Obama and the 64-year-old cleric. But U.S. officials have dropped hints that Obama and other top officials are ready for impromptu chats with Rouhani or his American-educated foreign minister, Mohammad Javad Zarif, that could open the way for bargaining on Iran's disputed nuclear program.

There are signs that Rouhani "is somebody who is looking to open dialogue with the West and with the United States in a way that we haven't seen in the past," Obama said in an interview on Telemundo. "So we should test it."

Obama has repeatedly signaled his willingness for direct contact, both in remarks and in a recent exchange of letters with Rouhani, who was elected in June after a campaign that included pledges to ease Iran's isolation and improve relations with the West.

Iran's most powerful figure, supreme leader Ayatollah Ali Khamenei, has long resisted compromise on the nuclear program. But with punitive sanctions increasingly squeezing the economy, he has signaled top-level support for the Rouhani mission, including allowing the release of 11 political prisoners. Most had been held since the government crackdown that followed Ahmadinejad's disputed reelection in 2009.

In an op-ed that appeared Friday in the Washington Post, Rouhani urged world leaders "to make the most of the mandate for prudent engagement that my people have given me, and to respond genuinely to my government's efforts to engage in constructive dialogue."

Whereas Ahmadinejad was often viewed as a carnival sideshow in his annual trips to New York, VIPs and journalists are scrambling to get a close look at Rouhani. During his visit, he has scheduled almost nonstop meetings with senior diplomats, news media executives, Iranian Americans and foreign policy heavyweights, including a speech sponsored by the Asia Society.

He will come accompanied by a Jewish Iranian legislator, Ciamak Morsadegh. Rouhani used his Twitter account this month to send best wishes to Jews celebrating the Rosh Hashana holiday, a move unimaginable under Ahmadinejad.

"After eight years of an erratic, unpredictable president who would say outlandish things, you have a normal person as the president of Iran," said Haleh Esfandiari, a former political prisoner under Ahmadinejad who now heads the Middle East program at the nonpartisan Woodrow Wilson International Center for Scholars in Washington. "He is centrist, he is a moderate, he tries to compromise — a word that did not exist in President Ahmadinejad's lexicon."

Rouhani's appeal — it's already being called "Rouhanimania" — is apparent in the huge demand for tickets to a dinner he will have with several hundred Iranian Americans in New York.

Two years ago, the Iranian mission to the U.N. canceled a similar dinner with Ahmadinejad when too few wanted to come. This time, the mission has been overwhelmed with requests to meet Rouhani or his foreign minister, according to a person familiar with the planning, who declined to be named.

Whether Rouhani is simply presenting a more moderate face to the world or is open to real compromise to end the nuclear dispute is still unclear.

Even his detractors predict he will radiate charm and avoid provocations. Although he is a true believer in the Islamic Revolution and a pillar of the Iranian national security apparatus, he is also pragmatic and intelligent. He speaks English well, having lived in Scotland in the 1990s as a PhD candidate.

It was Rouhani who arranged the Iranian government's sympathetic reaction after the terrorist attacks of Sept. 11, 2001. He also helped Washington reach out to opposition forces in Afghanistan and Iraq, both of which border Iran, after the U.S.-led invasions.

In his recent public comments and Twitter postings, Rouhani has tried to appeal to the West without upsetting hard-liners at home.